diff --git a/Dev.md b/Dev.md
index f859360..7077696 100644
--- a/Dev.md
+++ b/Dev.md
@@ -16,7 +16,8 @@ Views into the process of Tahoe hackery.
 
  * The [/tahoe-figleaf/current code coverage statistics] show which lines of code get exercised by the unit tests.
    * [/tahoe-figleaf Archived data] is also available.
-   * So is a [/tahoe-figleaf-graph/hanford.allmydata.com-tahoe_figleaf.html graph of code coverage over time].
+   * [/tahoe-figleaf-graph/hanford.allmydata.com-tahoe_figleaf.html this graph] shows how code coverage has changed over time, measuring what percentage of the [allmydata]source:src/allmydata codebase is covered.
+   * [/tahoe-figleaf-graph/hanford.allmydata.com-tahoe_figleaf2.html this one] measures the number of lines that are **not** covered, which gives better resolution than the percentage-wise graph
 
  * The [TestGrid](TestGrid) page contains usage statistics about the public test grid.